Composition material adapted to the plastic art



Patented May 29, 1928.

UNITED ST TES 1,671,230 PATENT OFFICE.

OLQTUB I. CHOSA, OI MILWAUKEE, WISCONSIN, ABSIGNOB TO THE CUTLER- H 1 Ir m. 00., O1 MILWAUKEE, WISCONSIN, A CORPORATION OF WISOONSIE,

COMPOSITION MATERIAL ADAPTED TO THE PLASTIC A'B'I.

I No Drawing.

This invention relates to composition materials adapted to the plasticart; also to methods of producing such materials.

In prior Patent No. 1,233,416, issued July 17, 1917, to William H.Steinberg, is disclosed a composition material comprising an inert baseor filler, a pol merizin or vulcanizin agent and a bin er inclu ing coaltar pitc stearine pitch, an animal or vegetable oil capable of,polymerization and a solvent of low boiling point, together .withmethods of producing such material.- Also in a prior application ofClarence A. Nash, filed July 19, 1920, Serial No. 397,181, are disclosedcertain improvements in the product and process of Steinberg.

The, present invention has among its ob- 'ectsv that of otherwise andfurther improv-.

mg theproduct set forth in said Steinberg patent.

Another object is that of providing initar proved and simplified methodsof producing materials adapted to the uses contemplated insaid'Steinberg patent.

Another object is that of roviding a novel and improved material a aptedto the plastic arts.

Another object is that of providing improved and simplified methods ofproducmg)such materia ther objects and advantages will hereinafterappear. While the materials and processes disclosed in said patent andalso the improved process and product disclosed in said application haveproven of great value and have been extensively used industrially, theprocesses aforenoted have been unduly compli- .cated, expensive and timeconsuming whereas by the new process herein contemplated it has beenfound possible not onl to simplify the method of production 0 thematerial as well as reduce the time, labor and expense involved inproduction thereof but also to produce a superior roduct.

According to the teaching of the Steinber patent, a relatively inertfiller material sue for example as asbestos, is impregnated with acomposition binder comprising among other ingredients approximately eual portions of stearine pitch and coal tar 1tch, these substancesconstitutin the maor constituents of the binder.. the application ofNash, a portion of the coal tar pitch is replaced by an asphaltic bodysuch Application filed J'un'e 1a, 1923. Serial No. 04 ,235.

for example as gilsonite whereas certain further variations andimprovements not herein important are contemplated.

.I Iowever, both said patent and-saidjappli- .catlon contemplate the usein the bmder aforesaid teach as an important step in their respectiveprocesses at of removing such free carbon which as stated is likely tobe precipitated to the exent of 30% b weight of the coal tar pitchemploye whereas in practice it is now known that this amount of freecarbon may and fr uently does ap roximate by weight of t e coal itc T isprocedure obviously involves loss of a relatively high percentage of thematerial since the carbon so removed is of little or no commercialvalue. Also the size s necessary for such removal are quite di cult,expensive and time consuming, since the carbon has a tendency to settleand adhere to the lower portions of the tank, still or the like in whichthe binder is formed, necessitating considerable labor for its removal,whereas the container is frequently very much damaged by the roughtreatment incident to such removal. According to the herein contemplatemethod, I am able to obviate entirely the aforementioned procedure forremoval of free carbon, whereas, as a result of the aforesaid method Iam also able to-obtain a product adapted to all or practically all usesto which the earlier products are applicable and moreover possessingadvantages thereover.v

Thus in accordance with the herein contemplated proceduresuitableprgiortions of stearine pltch and asphaltic y ma be broughttogether in the absence of coa tar pitch, or in the absence.of asufiicient quantity of the latter to involve recipitation of a materialquantity of car on under the treatment imposed, the resultant mixturebeing thereafter treated, under suitable eon- In those cases wherein arelatively inert filler, such for example as comminuted asbestos, isincorporated with the aforedescribed plastic material prior to moldingthereof the sulphur or other solidifying a cut may be preferably mixedwith such ler prior to incorporation.

The aforedescribed plastic material, preferably after incorporation witha suitable filler, is thereafter adapted to form givin treatmentpreferably under pressure, wit strong heat induration treatment,preferably after removal of the formed piece from the forminginstrumentality.

Durin such heat induration treatment the sulp ur or other solidifyingagent appears to act u on or with reference to certain of the ot erconstituents of the material, particularly the solidifiable oil or thelike, whereby the material of the piece is transformed into a hard anddurable condition, exhibiting superior strength with resistivity towardthe action of chemical agents .and solvents.

As typical of certain preferred methods of producing the herein contemlated roducts, the following steps may e emp oyed. Ap roximately 40parts of stearine pitch an approximately 60 parts of asphalt are scribedingredients may paratory to molding. Also it is preferable heatedtogether to a temperature of approximately. 500 degreesF. with stirringto effect anjintimate mixture 'ofsaid ingredients. The mixture isthereafter cooled to approximately 47 5 degrees F., whereuponsubstantially 10 parts of castor oil is added and the. mixture againstirred. Thereafter the mixture is permitted further to cool toapproximately? 200 degrees F. and thereafter approximately 25 parts ofbenzol is added and the mixture again thoroughly stirred.

For production of a moldm com ound, approximately 286 parts of t e aoredematerial, taken as a binder is .thorou hly mixed and incorporatedwith approx mately 1100 parts of a suitable filler such as asbestos, 66parts of sulphur and 22 parts of iron 'oxidebein added. Such mixing andincor oration o the foregoing facilitated by further additions of benzolupto or evensomewhat in excess of 100 parts. The mixture may be thendisintegrated, screened and subjected-to other desired known treatmentprethat anpappreciable interval of time, as

' for example twelve hours intervene bebeyond 24 hours at tweencompounding of the molding material and actual pressing thereof. Thematerial may be pressed in cool or cold dies under conditions similar tothose ordinarily imposed in treatment of analogous molding mixes.Following molding the material is subjected to stron heat treatmentwhich may cover a perio of hours up to or even temperatures which arepreferably elevated radually from approximately 200 degrees to a finaltemperature of about 500 degrees F.

Pieces produced in the manner aforede scribed are characterized by verysuperior strength andresistance to impact; Also it has been found thatsuch pieces undergo in general lesser and more uniform degrees ofshrinkage during cure than do pieces formed of materials prepared in theordinary ways, whereas the pressing qualities of the material are foundtobe superior.

While the aforementioned proportions of the various ingredients,articularly the stearine pitch and asphalt, ave been found to bedesirable and advantageous, it is nevertheless to be understood thatsuch proportions may vary rather widely, whereas, for certain specialpurposes radically different proportions may be found desirable. Furtherin special cases it has been found possible and also desirableto reducethe quantity of the asphalt practically or even actually to the point ofelimination thereof, whereas for other purpo es it has also been founddesirable similarly to decrease the stearine pitch content.

Thus a compound may be produced by mixing together, at approximately 475 F., 800 parts of asphalt and approximately 82 parts of castor oil, themixture being permitted to cool to about 200 F., and about 320 parts ofbenzol being thereafter added with stirring. Approximately 286 parts ofthe last desciibed-compound, taken as a binder, to-

arts of sulphur, 22 parts proportion of the solidifia 10 oil or t e likemay be varied between relatively wide limits.

Thus an-advantageous compound characterized by'high plasticity, superiormolding properties and relatively low and uniform shrinkage duringinduration may be produced b treating, in the manner described in therst of the foregoing examples, approximately 50 parts each of stearinepitch and asphalt, together with approximately parts of castor oil and asuitable quantity of benzol or the like and having 1nc0rporatedsubstantially the proportions of filler material and sulphur mentionedin the previous examples.

Such compound is well adapted to form giving treatment and strong heatinduration. It is of course to be understood that the proportions of thevarious ingredients stated in each of the foregoing examples are capableof considerable variation to adaptthe product tov special conditions anduses.

It is also to be understood that the terms stearine pitch, asphalt andothers employed herein are intended to designate the substancesobtainable commercially.

What Iclaim as new and desire to secure by Letters Patent is 1.Composition material adapted 'to the plastic art, comprising,approximately, .40 parts of stearine pitch, 60 parts of asphalt, 10parts of castor oil and parts of 'benzol, said material being capable oftreatment under influence of heat without involving precipitation of adeleterious quantity of free carbon.

2. A hard and substantially infusible and insoluble substance which isthe heat induration residuum of material comprising a -.binder formed ofapproximately 40 parts of stearine pitch, 60 parts of asphalt, 10 partsof castor oil and 25 to 100 parts of benzol, 286 parts of said binderbeing mixed with about 1100 parts of asbestos, 66 parts of sulphur, and22 parts of iron oxide, said binder being capable of treatment under influence of heat without involving precipitation of a deleterious bon.

3. The process, of producing composition material adapted to the plasticart, which comprises melting and mixing together about quantity of freecar 40 parts of stearine pitch and 60 parts of asphalt, cooling themixture and adding thereto a solidifiable oil, further cooling themixture and adding thereto a volatile sol-' comprises melting and mixingtogether about 40 parts of stearine pitch and parts of asphalt, coolingthe mixture and adding thereto 10 parts of a solidifiable oil, furthercooling the mixture and adding thereto at lease 25 parts of a volatilesolvent, said mixture being capable of such. treatment without involvingprecipitation of a deleterious quantity of free carbon, incorporatingwith about 286 parts of the mixture about 1100 parts of an inert fillermaterial, and incorporating about 66 parts of an agent adapted underinfluence of heat to promote induration of the product.

5. The process which comprises mixing together under conditions oftemperature control about 40 parts of stearine pitch, 60 parts ofasphalt, and 10 parts of a solidifiableoil, said mixture being capableof such treatment without involving precipitation of a deleteriousquantity of ree carbon, in corporating with about 286 parts of themixture about 1100 parts of a relatively inert filler, introducing about66 parts of sulphur and at least 25 parts of a volatile solvent,subjecting the product toa cold molding operation, andindurating theformed articles by strong heat treatment.

In wltness whereof, I have hereunto sub:

scribed my name.

CLETUS F. CHOSA.

